.box {
  width: 1000px;
  height: 200px;
  margin: 100px auto;
  border: 1px solid #000;
  overflow: hidden;
}
.box ul {
  margin: 0;
  padding: 0;
  display: flex;
  list-style: none;
  animation: cha 15s infinite linear ;
}
.box ul img {
  width: 400px;
  height: 200px;
}
@keyframes cha {
  0% {
    transform: translate(0);
  }
  100% {
    transform: translate(-1400px);
  }
}
